Abstract: The invention is an optoelectronic device and method of fabrication where at least two optical devices are formed on a single semiconductor substrate, with each optical device including an active region such as a multi-quantum well region. The active devices are spatially separated and optically coupled by a passive waveguide formed over the substrate which provides butt joints with the active regions. The butt joints can be optimized independently from the active regions thus improving yield.

Abstract: The invention is a semiconductor optical device and method of fabrication where the device includes an active region with an active layer having a first index of refraction, and a blocking region having a second, lower index of refraction. A semiconductor layer having an index of refraction higher than the blocking region is formed over both the active and blocking regions so that the semiconductor layer is in closer proximity to the active layer in areas not covered by the blocking region so as to decrease the difference between the effective index of refraction in the active region and the effective refractive index of the blocking region. Such devices are particularly useful for pumping optical amplifiers since greater power can be achieved while maintaining single mode emission.

Abstract: The present invention provides an optoelectronic device and a method of manufacture therefor, that prevents dopant diffusion and controls the dopant concentration therein. The optoelectronic device includes an active region formed over a substrate, and an interface barrier layer and barrier layer located over the active region. The optoelectronic device further includes an upper cladding layer located over the interface barrier layer and the barrier layer. In an exemplary embodiment of the invention, the interface barrier layer is an indium phosphide interface barrier layer and the barrier layer is an indium gallium arsenide phosphide barrier layer.